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Pediatrics: Discovering more about how watching TV hurts preschoolers' sleep

Watching violent TV during the day -- or any TV during the evening hours --… (Tim Boyle / Getty Images )

Three-to-5-year-old kids who watch violent or scary media content, or who watch more TV during evening hours, are increasingly likely to have sleep problems, according to research published Monday in the journal Pediatrics.

Though previous studies had shown that watching television, playing video games or using a computer can interfere with preschoolers' sleep, Michelle M. Garrison of the Seattle Children's Research Institute and coauthors wrote, this work sheds light on how what children watch, when they watch and with whom they watch contribute to sleeping problems.

The team reviewed 612 families' "media diaries" to determine where, what and when kids watched over a seven-day period. They also looked at survey data indicating whether the children had sleep problems such as trouble falling asleep, waking up during the night, nightmares, trouble waking up in the morning and daytime tiredness. They also looked at other aspects of the kids' behavior sometimes associated with sleep disturbance, including anxiety and aggressive behavior.

On average, study participants reported getting 72.9 minutes of media screen time daily. Just over 14 of those minutes were after 7 p.m. Eighteen percent of the parents reported at least one sleep problem. Violent content and evening TV were associated with increased sleep problems. Nonviolent daytime shows didn't seem to have an effect on preschoolers' sleep, the authors found. Whether kids watched TV with an adult didn't seem to make a difference, either.

Not surprisingly, kids who had TVs in their bedrooms -- about 10% of the survey participants -- watched more TV, about 40 additional minutes per day, and reported more trouble with nightmares, with falling asleep and with daytime tiredness.